UNIT
7: THERMAL PROPERTIES OF MATTER
 Temperature (
9 Periods )
 Temperature
scales.
Practical
thermometers.
- liquid in glass
- constant volume gas thermometer
- electrical resistance
- thermocouples
- pyrometers
Absolute
temperature scale.
Assessment objectives
By the end of this topic, the student should be
able to:
- List the different types of thermometers available
for measurement
of temperature and the thermometric properties used.
- Describe the steps involved in setting up a celcius
scale of temperature.
- Describe the structure and action of the liquid-
in- glass, constant
volume gas thermometer, platinum resistance and thermocouple
thermometers.
- Perform and describe measurement of temperature by
the thermistor.
- Perform and describe measurement of temperature using
a resistance of
an insulated copper coil and metre bridge.
- Perform and describe measurement of temperature using
thermocouple.
- Compare temperature measured thermometers using
different thermometric
properties.
- State the relative merits (advantages and disadvantages)
of different
thermometers.
- Define the absolute temperature scale.
- Convert temperatures in degrees celcius to absolute
temperatures.
- Describe and explain the structure and mode of operation
of the optical
and total radiation pyrometers.
7.2
Specific Heat Capacity
(9 Periods)
Definition and
its measurement.
- method of mixtures; Newton's law of cooling;
cooling corrections
- electrical methods including; the continuous
flow method for liquids.
Assessment objectives
By the end of this topic, the student should be
able to:
- Define specific heat capacity.
- Perform and describe an experiment to determine the
specific heat capacity
of a solid and a liquid by the method of mixtures.
- Explain what cooling correction is.
- Obtain a cooling correction in the method of mixtures
for the determination
of the specific heat capacity of a poor conductor of heat
like rubber using
the graphical method.
- Perform and describe an experiment to determine the
specific heat capacities
of solids and liquids by electrical methods including
the continuous flow method.
- State the advantages and disadvantages of the method
of mixtures and the
continuous flow method.
- Solve problems involving heat loss and gain.
- Perfom and describe an experiment for comparison
of specific heat
capacities of liquids using Newton's law of cooling.
7.3
Change of state. (
9 Periods )
Molecular theory
explanation of melting, evaporaiton and boiling.
Specific latent
heat of fusion and vaporization.
Internal and external latent heat of
vaporisation.
Electrical method
of measuring specific latent heat of vaporization.
Assessment objectives
By the end of this topic, the student should be
able to:
- Explain melting, evaporation and boiling using molecular
theory.
- Define specific latents of fusion and vaporization.
- Perform and describe experiments for determination
of specific
latent heats using method of mixtures.
- Perform and describe an electrical method for determination
of
specific latent heats of fusion and vaporization.
- Solve problems involving changes of state and changes
in temperature.
7.4
Expansion of gases. (5
Periods)
The gas laws and
the equation PV = NkBT or nRT
Pressure and volume
coefficients of expansion.
Assessment objectives
By the end of this topic, the student should be
able to:
- State Boyle's, Charles's and the pressure laws.
- Perform and describe experiments to verify the laws.
- Derive and use the equation PV = NkBT
or PV = nRT
- Define pressure and volume coefficients of expansion
and show that
they are equal.
7.5
Kinetic Theory of gases.
(10 Periods)
Brownian motion
and evidence of molecules
Postulates about
the molecules of an ideal gas.
Derivation of P
= 1 r <c2> and comparison with
PV = NkBT or nRT.
3
Deduction from
the ideal gas equation.
- Avogadros hypothesis
- Graham's law of diffusion.
- Dalton's law of partial pressures.
Real gases.
- Van der Waal's equation of state.
( P + a )(V - b) = RT
v2
P vs V curves for a real gas.
- critical temperature.
Saturated and unsaturated
vapours, saturated vapour pressure.
- connection with boiling of a liquid.
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